Refrigerating apparatus



Aug. ll, 1942. y D H. REEVES REFRIGERATING APPARATUS Filed March 19, 1941 Patented' Aug. 11, 1942 nnrarcsmrmc APPARATUS e Donald H. Reeves,4 Dayton, 0h10; lllrlior to (zien.-l

eral Motors Corporation, Dayton, Ohio, a corporation of Delaware Application March 19, 1941, Serial No. 384,045

6 Claims. (Cl. 62-116) This invention relates to refrigerating apparatus and more particularly .to a two-temperature refrigerator cabinet.

Recently there has been placed on the market a type of refrigerator commonly referred to as a "Cold-Wallrefrigerator. This type refrigerator diil'ers from conventional household refrigerators in that a partition is provided within the refrigerator chamber for dividing the interior thereof into upper and lower food storage spaces or compartments. In this type of refrigerator a secondary refrigerant circuit forming means has a portion thereof extending over or wrapped around the wallsof the lower compartment and has another portion thereof disposed in contact or in intimate heat exchange relationship with an evaporator or freezer coil, located'in the upper compartment, of. a closed primary refrigerating system. It has, of course, been preferable to construct the secondary circuitv as simple as possible so as to materially minimise manufacturing cost of the refrigerator. The secondary circuit of such refrigerators has been secondary refrigerating circuit with a primary refrigerating'system whereby the upper compartment of a'cabinet of a refrigerating appa-` yratus can be cooled by the evaporating portion of a secondary refrigerating circuit without employing valvesl or pumps and the like in the secondary circuit.

A further and morespecific object of myinvention is to associate a primary refrigerating system, having two evaporators or two evaporating portions disposed one above the other, with a two-compartment refrigerator cabinet and wherein the lowermost of the primary evaporators is employed to'cool the lower compartment of the cabinet and the other or uppermost primary evaporator is utilized to render a seccompanying drawing, wherein a preferred form devoid of valves and is therefore a continuously `open circuit wherein the volatile refrigerating uid flows freelythroughout the circuit. Consequently, it has been necessary, in obtaining the proper circulation of refrigerating fluid in such circuits, to cool the lower food storage compartment of the cabinet by the secondary circuit and to cool the upper compartment by the evaporator of the primary refrigerating system. Should this practice be reversed in an attempt to'. cool the upper compartment by the secondary circuit and the lower compartment by the evaporator of a primary refrigerating system, then -valved heat pumps or the like are necessary to lift liquid refrigerant upwardly from the lower portion of the secondary circuit to the upper evaporator portion thereof. Such valved heat pumps in a secondary circuit in addition to being expensive are a source of continual trouble. Therefore, I contemplate the cooling of a lower food storage compartment of a two-temperature refrigerator,

cabinet by an evaporator of a primary refrigerating system and the cooling of the upper ondary refrigerant circuit, devoid of valves and/or heat pumps, effective to coolthe upper -compartment of the cabinet.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the acof the present inventionis clearly shown.

In the drawing:

Fig. 1 is a front view of a refrigerating apparatus having my invention embodied therein;

.Fig. 2 is an enlarged fragmentary, vertical, sectional view of the refrigerator shown in Fig. 1: and

Fig. 3 is a diagrammatic showing of the refrigerating systems adapted to be associated compartment thereof in a practical and improved manner by a secondary refrigerant cir` cuit associated with the primary refrigerating system and without the use of valved heat pumps or troublesome devices interposed in the circuit.

An object of my invention is to provide an with the refrigerator lcabinet disclosed in Figs. 1 and 2..

Referring tothe drawing, for illustrating my invention, I have shown in Fig. 1 thereof a re-v frigerating apparatus of the two-temperaturev household type. A cabinet I0 has a plurality of outer metal panels or walls II and an inner metal liner member .I 2 forming a chamber within Any suitable or desirable insulating material I4 (see Fig. 2) may be disposed bethe cabinet.

tween the liner I2 and the walls II to insulate the chamber. Liner member I2 has an aperture therein registering with an aperture formed in the walls II in the front of cabinet I0 to provide an access opening for the chamber.

This access opening i's normally closed by an ine sulated door structure I5. The chamber within cabinet I0 is .divided into an upper food storage space or compartment Il. and a lower food improved two-temperature refrigeratorvcabinet'.

Another object of my invention is to provide animproved arrangement or association of a storage spaceor compartment I8 by a glass plate or the like partition I8. Partition I9 has arubberor the like gasket'member 2l secured to all four edges thereof and the gasket 2| engages the three vertical. walls of-liner `I2 vand the inner face of door I5 to isolate the compartments I1 and I8 from one another; hydrators 23 may be mounted in any suitable or desirable manner within the top portion of the upper food compartment The outer cabinet walls depend below the insulated chamber and form a machine compartment 24 (see Fig. 2) in the bottom of cabinet I0 for housing a refrigerant liquefying and circulating unit. This machine compartment is closed at the front of the cabinet by acover or door 26.` l

A primary refrigerating system .associated with the refrigerating apparatus or refrigerator cabinet includes an evaporating part or evaporator 3|, embedded in the insulation |4 at the upper part of cabinetI Ill and another or second evaporatorV 32 located below the levelof evaporator 3| and disposed within the lower compartment I8. The refrigerant liquefying and circulating unit of the primary refrigerating system is usually mounted in machine compartment 24 'and comprises a sealed motor-compressor unit 33 and a condenser 34 (see Fig. 3)'. Refrigerant compressed by the compressor of unit 33 is forwarded under pressure, through a pipe 38, to condenser 34 where it is cooled in any suitable or desirable manner and liqueed. The'liquid refrigerant is circulated to evaporator v3| by way of pipe 31' under control of a suitable restrictor device 38. Restrictor 38 causes some-of the liquid refrigerant to expand upon entering evaporator 3| and this expanding or. evaporating refrigerant produces a refrigerating effect for'a purpose to be hereinafter described. Ay small diametered restricting tube or pipe 33, leading from evaporator 3| to evaporator 32conveys the A remainder of the liquid refrigerant admitted to evaporator 3| along with therefrigerant evaporated therein to the evaporator 32. -It is to be Vegetable storage v ble bellows (not shown) contained within a control switch 48 which lmay be of conventional snap acting construction. Actuation of mechanism of switch 48 controls an electric circuit to the unit 33 to start and/or stop operation of the motor, and consequently the compressor of the primary refrigerating system. v

. A closed secondary circuit containing a volatile liquid refrigerant is associated with the refrigerator Ill and comprises a refrigerant condensing portion 5| in the form of a conduit loop secured to a metal plate 52. The plate 52, to which the `condenser of the secondary circuitis secured, is clamped or secured in any suitable or desirable manner in'iace to face contact with the plate 42, carrying the refrigerant evaporating part or evaporator 3| of the primary refrigerating` system so as to be in intimate thermal heat exchange relationship therewith. Plates 42 and 52 are located above the level of the top of liner I2 and a liquid feeding'conduit 63 is connected with and depends from the condenser.

-of the secondary circuit for forwarding conorating portion I4 of the secondary circuit comunderstood that while I have disclosed the Along small diameteredrestricting tube 38 for controlling or conveying both gaseous and liquid refrigerant from evaporator 3| to evaporator 32, other forms of restrictors or an expansion valve can be used for this purpose. Refrigerant evaporated within evaporator 32 is withdrawn therefrom by the compressor of the motor-compressor unit 33 through a return conduit 4|. Evapora- 'tor 3| is in the form of a nat serpentinecoil secured to a metal plate 42 and the refrigeratying effect produced by this evaporator or this part of the primary refrigerating system is utilized to render a secondary refrigerant circuit, to be hereinafter more fully described, effective to lproduce refrigeration. The evaporator 32 is preferably of the conventional sheet metal type and is mounted in any suitable or desirable] manner in the lower food storage compartment I8 o f cabinet I3 so as to cool this compartment to a low temperature. Ihe temperature of evaporator 32 is at all times maintained below freezing circuit, enters the condenser loop II by way of conduit I3 and trap Il. This evaporated refrigin order to freeze water or other substances placed in trays and located thereon. The cooling compartment I3 at such low temperature causes frost to form on the walls of the primary evaporator 32 whichalso causes dehydration of the air within the compartment and the main'- tenance of a low relative humidity therein.

Starting and stopping of the electricmotor of the motor-compressor unit 33'may be,carried out in response to the temperature of the evapora- Y tor 32. Thus I mount a thermostatic bulb Ion a wall of evaporator 32 and connect this bulb,

' by4 a pipe-41, with an expansible and' contractidensed liquid refrigerant to an evaporating-portion I4 of the circuit. This evaporator or evapprises a plurality of conduit loopssecured to and extending over the outer surface of liner I2 so as to substantially traversethe top, back and side walls of the upper food compartment I1 of cabinet III.l A conduit 33 connects the evaporating portion or loops 54 of the secondary circuit with the condenser II thereof and. has a goose-neck trap 38 formed therein adjacent the condenser 5I as is customary in such systems to prevent 'any liquid -condensing in the condenser 3| from It W11] draining directly into the conduit 55. be noted that the secondary circuit is disposed below -the level of the first evaporator 3| of the primary refrigerating systemA andY that the refrigerant evaporating portion 54 of the secondarycircuit is located intermediate the level of the two primary evaporators 3| and 32 or above the evaporator 32. Volatile refrigerant evaporating within evaporator I4 of the secondary circuit cools the walls of the upper food storage compartment I I of cabinet I8 and maintains the interior of this compartment at a temperature above freezing. The interior of compartment I1 is inherentlyV `maintained between certain temperature limits in accordance with` the normal temperature limits of the primary evaporator 32 and consequently the temperature of primary evaporator 3| due to the association of .condenser 3| of the secondary circuit with' evaporator 3|. Refrigerant, after evaporating and ilowing upwardly in the loops I4 -of the secondary erant'is condensed'and liquefied by the refrigerating effect or lowtemperature of the primary evaporator 3| and the liquefied refrigerant then nows downwardly from the condenser 3| .by way'of the liquid-feeding conduit to the lowermost evaporator loops I4. In a structure of the type disclosed. itis the purpose of partition I3 to divide the cabinet chainber into two compartments wherein the one or lower 'compartment I8 is maintainedy at a low temperature and low .relative humidity'in the ymanner describedand wherein the'fother or upper .compartment is ymaintained at a highertem'- perature, and consequentlyhigh humidity for providing 'a two-ternperotur'e' cabinet for' the storage -of various food products. 1

mary refrigerating system in a novel manner to provide for the cooling of the upper food storage compartment of a refrigerator cabinet to a higher temperature than the temperature of a lowercompartment thereof cooled by the evaporator of the primary system. This is, in the present disclosure, accomplished byv a secondary circuit which is devoidof valves or heat pumps to thereby provide a refrigerating apparatus that is simple in constructiompractical, of low manufacturing costs and efficient in operation.

The contact between the one primary evaporator and the condenser of the secondary circuit is predetermined so as to insure the maintenance of a substantially constant temperature and high humidity within the high temperature upper food storage compartment of the refrigerator cabinet, while the second' evaporator freezes water into ice and maintains the low-temperature lower food storage compartment between its predetermined desired low temperature limits. It will be understood that by associating the condenser of the secondary circuit with a refrigerant evaporating portion of the primary system disposed above the primary evaporator' employed for cooling the lower of the compartments of the refrigerator cabinet, the condensing portion and the evaporating portion of the secondary circuit are normally in continuously open communication with one another and function in the well known and conventional manner to cool the upper compartment of the cabinet. This secondary circuit,v being devoid of heat pumps .and the like, is of low manufacturing costs as comparedto other complicated and troublesome secondary circuits employed to cool a come partment above a compartment in which a primary evaporator is located.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope o'f the claims which follow.

What is claimed is as follows:

1. A refrigerating apparatus comprising in combination, a cabinet having an upper food storage'compartment and alower food storage compartment therein, a closed primary refrigerating system associated with said cabinet and including an evaporator disposed in said lower food compartment for cooling same, a closed secondary refrigerating circuit containing a volatile liquid and including a condensing porship with said lowerfood compartment for cooling same, a closed secondary refrigerating circuit containing a volatile liquid, said secondary circuit including a condensing portion in intimate heat exchange relationship with said ilrst primary evaporator andan evaporating portion located above Asaid secondaryvprimary evaporator and disposed in heat exchange relationshipv with said upper food4 compartment for cooling same; and means for circulating refrigerating uid to and from said evaporator of the closed primary refrigerating system.

3. A refrigerating apparatus comprising in combination, a cabinet having la plurality of walls forming a 'chamber therein, said chamber being provided with an access opening normally closed by a door, means cooperating withthe inner face of said vdoor and with the upright walls of said chamber for dividing the chamber into an upper food storage compartment and a lower food storage compartment, a closed primary refrigerating syst'em including a -rst evaporator4 in the upper portion of said cabinet and a second Ievaporator disposed in heat exchange relationship with said lower` food compartment for cooling same, a closed secondary refrigerating circuit including a condensing por tion in intimate heat exchange relationship with said first primary evaporator and an evaporating portion located above said second primary evaporator and disposed in heat exchange relationship with saidupper feed compartment for cooling same, and means for circulating refrigerating Viiuid to and from said evaporators of the closed .in the top portion of said cabinet and a second evaporator disposed within said lower compartment for cooling same, a closed secondary re frigerating circuit containing a volatile liquid. said secondary circuit including a condensing portion in intimate heat exchange relationship with said first primary evaporator and an evaporating portion located above said second primary evapoy rator and. disposed in intimate thermal contact with Walls of said upper compartment for cooltion associated with a part of said primary refrigerating system disposed above said evaporator thereof, said secondary circuit also including an continuously open communication with one evaporating portion extending over walls of said another and means for circulating refrigerating uid to and from said evaporator of the closed primary refrigerating system. f

2. A refrigerating apparatus comprising in combination, a cabinet having an upper food storage compartment and ay lower food storage compartment therein, a closed primary refrigerating system including a iirst evaporator in the 'upper portion of said cabinet andv a second evaporator disposed in heat exchange relation-i I5 ing the interior thereof, and means for circulating refrigerating uid to and from'said evapo-l rators of thev closed primaryI refrigerating system.

5. A refrigerating' apparatus comprising in combination, a cabinet having a plurality of walls forming a'chamber therein, said chamber being provided with an access opening normally closed by a door, means cooperating with the inner face of said door and with the upright walls of said chamber for dividing the chamber into an upper food storage compartment and a lower food storage compartment,` a closed primary refrigerat- .ing system including a first evaporator disposed exteriorly of said upper compartment and located in the top portion of said cabinetand a second evaporator disposed within said lower compartment for cooling same, a closed secondary refrigeratingcircuit containing a volatile liquid, said secondary circuit including a condensing portion in intimate heat exchange relationship l with said first` primary evaporator and an evaporating portion located above said second primary evaporator and disposed in' intimate thermal contact with walls of said upper compartment closed primary refrigerating system having a low. pressure side including an evaporator disposed in heat exchange relation with said lower compartment, a closed secondary refrigerating circuit including a heat dissipating portion and a heat absorbing portion disposed below said heat dissipating portion, said heat dissipating portion-of i said circuit being in heat exchange relation with thelow pressure side of 'said primary refrigerating system at a point above the .primary evaporator, said heat absorbing portion of said circuit being disposed in heat" exchange relation with said upper food compartment, said secondary circuit being 'normally maintained at substantially the same pressure throughout the heat dissipating and heat absorbing portions thereof,

4and means for circulating refrigerating iiuid to and from said evaporator oi' the closed primary refrigerating system. DONALD I-I. REEVES. 

